PSG team management could not collect anything great from a player like Lionel Messi. In fact, I think the PSC team coach does not know how to play Lionel Messi. However, if Kylian Mbappe ever leaves PSG, the team will collapse.
In general, PSG has never depended on just two players and if PSG did depend on just two players, it was clear that the team would collapse because the team did not respect the other players in the team. But for next season what PSG really needs is a great young player even if he's not a star, because the PSG team can't keep hoping for one or two star players who aren't young anymore. So PSG must be able to find great young players in the transfer market before next season starts.
I won't go into the argument about whether PSG is dependent on only two players. I would say PSG have had a lot of star players but their performances have been erratic. Since their overall performance was erratic, it didn't matter if their team relied on just two players. Bonding between players was weak at PSG. If they want to do well next season, PSG management should revamp the entire squad. If not, I think the team will be eliminated from the first round of the Champions League next season.
Messi has left the PSG team. Because Messi was not able to achieve much in this team. The aim of adding Lionel Messi to the team was to do something great in the Champions League. But that purpose was not fulfilled. But football fans are hoping that Messi will do something great at the next club.